FLAMMABILIT Y T ESTING
“ The processes
will completely
restructure
flammability
regulations”
aircraftinteriorsinternational.com
NOVEMBER 2019 047
A Notice of Proposed Rulemaking (NPRM)
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published in July represents a significant reform
of the aviation industry’s fire testing processes,
and is part of the general trend away from prescriptive
to performance-based rulemaking.
The broad scope of the proposed rule raises serious
questions about whether the regulator is moving too far
away from core safety principles in an effort to simplify
the approvals process, especially as new technologies arise
approach.
critical for the components in question.
as a sidewall), and the material type
(elastomeric materials, for example). This
approach has led to problems, including
same component depending on what material it is made
from; and ambiguous requirements for components not
explicitly listed in §25.853 or Appendix F part I of part
25. These ambiguous requirements for components not
explicitly listed have resulted in the requirements of
§25.853 or Appendix F, part I of part 25 becoming
obsolete whenever materials change, or incomplete when
components have been developed after the regulation
and Appendix F of part 25 were issued.”
The NPRM published in July reflects the ongoing
work of ARAC and the Flammability Working Group,
but its broad scope comes as something of a surprise.
While the original comment period on the NPRM was
set to close on 1 October 2019, requests for extension of
the comment period were filed in September from OEMs
including Airbus, Boeing, Bombardier, Gulfstream and
Embraer, as well as Safran and Sekisui SPI. Their request
for more time stems from the deep implications of this
NPRM for all cabin interiors components.
The International Coordinating Committee of
Aerospace Industry Associations (ICCAIA) also filed
a request for an extension to the comment period.
In a letter signed by Simon Lie, chair of the ICCAIA
Airworthiness Committee and Joerg Lieberwirth,
coordinator of the ICCAIA Cabin Safety working group,
the ICCAIA stated: “The proposed changes are substantial
safety and materials flammability.
Morgan has worked extensively with
testing
WET TESTING UNDERWAY IN
SAFRAN’S FLAMMABILITY LAB.
PHOTO: FRANK ROGOZIENSKI /
CAPA PICTURES / SAFRAN
that were not previously accounted for in regulations.
The NPRM follows ARAC (Aviation Rulemaking
Advisory Committee) recommendations made in 2015
to simplify flammability through a “threat-based”
As the FAA explained in 2015, when detailing
determinations of the ARAC Materials Flammability
Working Group: “By ‘threat based’, the FAA means
the flammability requirements use a more realistic
test method based on the type of fire hazard most
Historically, these requirements have been based
on an analysis of the type of threat, the usage
of the potentially flammable material (such
multiple requirements applying to the same
component; conflicting requirements for the
and include new requirements, changes to the regulation
from a prescriptive regulation to a performance-based
regulation, and affect all parts within the fuselage across
interiors, structures and systems designs. Under the
proposed rule, the compliance processes will completely
restructure the flammability regulations and the processes
required to show compliance, and the 90-day comment
period is not adequate to properly assess and
coordinate the potential impact to design,
materials and certification implementation.”
First to comment on the NPRM, shortly
after its publication in July, was Dr
Alexander B. Morgan, group leader for
energy and environmental sciences at the
University of Dayton Research Institute
(UDRI), a research scientist who has
over 22 years of experience in fire
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